Bioacoustics of Atmetochilus fossor

Description. Female ( Neotype , ARA-2018-132, CUMZ): Body ( Fig. 6A ), length 25. Color in nature: Carapace red. Chelicerae and all legs dark brown. Upper abdomen grey with pale white spots and ventral abdomen white. Color in alcohol: Carapace red. Chelicerae and legs dark brown. Upper abdomen grey with pale spots and similar on ventral abdomen. Carapace ( Fig. 6B ): 10.60 long, 8.75 wide. Chelicerae 4.38 long. Eyes ( Fig. 6C ): tubercle with 2 rows on low mound, 4 eyes in each row. Anterior row procurved, posterior row slightly recurved. Eye sizes and interdistances: AME 1.30, AME-AME 0.50, ALE 1.60, ALE-ALE 4.40, PME 1.00, PME-PME 2.90, PLE 2.90, PLE-PLE 4.70, AME-ALE 1.00, AME-PME 0.30, AME-PLE 1.00, ALE-PME 1.00, ALE-PLE 1.80, PME-PLE 0 (contiguous). Eye to fovea 6.88. Fovea ( Fig. 6B ): strongly procurved to U-shaped, medially straight. 3 rows of setae in fovea. “Rastellum” of about 15 robust down-curved setae on anterior margin of chelicerae. Cheliceral furrow with 7 promarginal teeth and mesobasal denticles present. Fang ventrally smooth without teeth. Stridulating strikers absent. Labium ( Fig. 6D ): labium 1.50 long, 1.20 wide without cuspules. Maxillae ( Fig. 6D ) 4.25 long, 2.00 wide with 42 tiny cuspules each on proximal anterior lobe. Sternum ( Fig. 1C ): 5.16 long, 4.50 wide. Posterior and medial sternal sigilla centrally confluent, anterior sigilla small in upper margin. Spination: Palp: tibia, v3, patella, p1, tibia, p1, tarsus scopula on venter, v2. Leg I: femur, p1, patella, p1, tibia, v2, metatarsus scopula cover entire but thin at base, tarsus scopula cover entire, without spines. Leg II: femur, p1, patella, p2, metatarsus scopula on its distal half, v2 p1, tarsus scopula cover entire. Leg III: patella with group of around 10 short hard setae on dorsal, tibia, v1 r2 p4 d1, metatarsus with 21 spines, v3 r4 p8 d6, palp without scopula and spine. leg IV: patella with many short hard setae on dorsal as same as femur, tibia, v3 p1, metatarsus has 15 spines, v3 r3 p9. Preening combs on distal ventral of metatarsi II–IV. Legs ( Table 3 ), formula: 4123. Femur Patella Tibia Metatarsus Tarsus Total Palp 4.98 2.70 2.75 - 3.18 13.61 Leg I 7.84 4.20 5.10 4.80 2.70 24.64 Leg II 6.64 4.00 4.40 4.00 2.40 21.44 Leg III 5.40 3.30 3.00 3.90 2.40 18.00 Leg IV 8.70 4.30 5.40 7.80 2.60 28.80 Scopula: entire on tarsus of palp and metatarsus I, relatively short, sparse cover on distal half on metatarsus II, absent on tarsi III and IV, metatarsi III and IV, tibiae and femora I–IV. Trichobothria: one zigzag row of 8–14 on tarsi I–IV, one row of 6–16 on metatarsi I–IV and two rows, each of 5–8 on tibiae I, III. Claw: 1 row of teeth on prolateral edge of palpal claw. 2 rows of teeth on both paired claws of legs I–IV but different number including 3 teeth on inner side, 5–7 teeth on outer side of leg I, 2 teeth on inner side, 5–6 teeth on outer side of leg II, 2 teeth on inner side, 3 teeth on outer side of leg III and one tooth on inner side, 3 teeth on outer side of leg IV. Spermathecae ( Fig. 11A ): head of spermathecae spherical with cap darkly sclerotized, stalk 0.7 mm , base 1.1 mm stalk base wider than tip. Spinnerets: PMS: 1.20 long, diameter 0.15. PLS: 2.52 long, 0.20 diameter, length of basal, medial and apical segments 1.20, 0.60, 0.72; apical segment digitiform.